Car coupler



w. J. METZGER CAR COUPLER Filed July 31, 1957 Aug. 9, 1960 \llllllll INVENTOR.

' WILLIAM J METZGER Arramycv United States Patent 1C Patented Aug. 9, 1960 Filed July 31, .1957, Ser. :No. 615,561

'6 Claims. 7 01. 2 11-144 The present invention relates to amomatically-loclcing knuckle-type railway car couplers and particularly to an improved knuckle-throwing mechanism for couplers of this type.

In such couplers, as typified by the'A.A.R. Standard E Coupler, a knuckle pivotally mounted in the front portion of the coupler head is swung from a coupler-locked position to a coupler-open position by :a two-armed knuckle thrower pivoted at the junction of the arms. Coupling-opening action is imparted to the thrower by a lock which may move in its lengthwise direction in a chamber provided within the head. The chamber and the lock are relatively contoured so that the lock may pivot as it approaches the head or upper end of the chamber, causing a lower leg portion of the lock to swing rearwardly and horizontally against one arm of the thrower and the other arm thereof to engage a tail portion of the knuckle.

Because the lock leg swings in a somewhat upward arcuate path to engage and actuate the thrower the latter is subjected to an upward as well as horizontal force.

' vertical axis. The upper bearing of the coupler head 2 retains the thrower in operative positions in any orientation of the coupler.

The foregoing objects are achieved in a knuckle coupler,broadly speaking, "by providing a knuckle thrower having an npperxtrunnion and a lower trunnion, both of which comprise arcuate coaxial'surfaceszand further providing in the head @ofthe coupler amounting comprising an upper bearing and a lower bearing in relative alignment for engaging the 'trunnions and supporting the thrower for pivotal movement about a normally generally comprises an arcuate section of not greater than 180 degrees in angular length and an end-thrust surface extending radially inwardly from the upper end of the arcuate surface adapted for engaging the end surface of the upper trunnion. The 'lower bearin-g surface is substan- The essential purpose of turning the thrower about its normally vertical axis is readily accomplished but the vertical force tends to lift the thrower in its axial direction.' The horizontal force drives the trunnions backwardly against upper and lower bearing surfaces spaced to receive the trunnions. As the thrower is not subject to any appreciable force in a forward direction, there is no need for a forward lateral portion of the upper bearing and the bearing provided may be of arcuate cylindrical or conical shape, having an angular length of less than 180 degrees and usually about 90 degrees or less.

Because of the lift exerted on the thrower, an end thrust bearing isneeded to retain the thrower in an operative ambit. The bearing conventionally provided for this purpose is a horizontal surface extending radially from the lower end of the upper lateral bearing at a level adapting it to engage the retainer or safety lug of the thrower. Thislu-g, in the conventional coupler, is an extension of the knuckle-throwing arm and extends partly around the rear of theaxial portion of the thrower. It has recently been observed that considerable resistance to manual operation is attributable to the friction in the conventional thrust bearing arrangement just described.

It is an important object of this invention to substantially reduce the effort needed for manual operation of a knuckle-type coupler.

'Another object is to provide bearing structure for a knuckle thrower which imposes substantially less frictional drag in the movement of the thrower.

It is also an object to combine an improved bearing 7 mounting for a thrower and a member for absorbing bufiing forces in a single modification of the coupler structure.

Still another object is to provide a mounting for a knuckle thrower within a coupler of reducedfrictional v drag which permits-facile removal of the thrower and tially complementary to the lateral surface of the lower trunnion but, in the preferred embodiment, is slightly larger :in circumferencethan the lower trunnion to provide clearance whereby the thrower may be tilted away from the 'arcuate section of the upper bearing and lifted upwardly and out of the lower bearing without interference with the inner periphery of the end-thrust surface of the upper bearing.

The construction of the thrower and the bearing structureof the coupler head is such that during the knucklethrowing operation, .the upper trunnion of the thrower engages the arcuate lateral'surface of the upper bearing normally as the result of backward movement of the thrower and the thrower is lifted to bring about engagement of the end surface of the upper trunnion with the end-thrust surface of the upper bearing. .The thrower and the bearing surfaces are interrelated so that the safety lug normally provided on a thrower in the conventional coupler and incorporated in the preferred embodiment of this invention does not engage the overhangingsafety abutment of the coupler head when the end-thrust surface of .the upper bearing is engaged.

Fig. 1 is a fragmentary plan view in section illustrating a knuckle-type coupler in the coupler-locked position;

Fig. la is a fragmentary view asobserved in the direction ofthe arrow 1A of Fig. 1.

Fig. 2 is a fragmentary plan view in section illustrating the coupler in fully knuckle-thrown position;

Fig. 3 is a fragmentary plan view in section of the coupler of Figs. 1 and 2 with the knuckle and the lock removed, and the thrower positioned for being lifted out of its lower bearing;

Fig. 4 is a fragmentary elevation in section taken along line IVIV of Fig. 1;

'Fig. 5 is a fragmentary elevation in section taken along line V-V of Fig. 2;

Fig. 6 is a fragmentary elevation in section taken along line VIVI of Fig. 3;

Fig. 7 is a fragmentary perspective view illustrating a modified upper bearing and one type of axial element of a thrower;

Fig. 8 illustrates in fragmentary perspective view a modified type of axial element of a thrower.

In the drawing, Figs. 1 and 4 relate to thecouplerclosed position of a coupler wherein a knuckle 3 is secured between the sidewall 4- of the coupler head and a lock 5. A thrower 6 is shown disposed in its normally inoperative position to which it is returned and confined by a thrower pad 7 on the knuckle. In this position, the top pulling lug 8 of the knuckle engages a side surface of the laterally protruding lobe '9 of the lock 5. The lock is seated'on the knuckle tail by engagement of the undersurface of the lobe 9 with a small portion 10 of the knuckle tail.

Integral with the coupler head 15 is an L-shaped lug like projection (see Fig. 1a) comprising a bufiing-..lug

17, and a shelf 18 providing an arcuate bearing surface I 1'9 (upper bearing surface of the head) for engaging the lateral cylindrical surface of an upper trunnion 20 of the thrower 6. The shelf 18 comprises also an arcuate flange 21 extending radially inwardly from the upper edge, and toward the axis of the surface 19. The flange 21 extends inwardly approximately one-thirdor one-half of the radius of the surface 19 in order that, through the use of the clearance provided in the cylindrical bearing surface 23a (lower bearing surface of the head) forming the hole 23 which receives the lower trunnion 24, the thrower may be tilted forwardly away from the surface 19 and moved upwardly past the flange 21 in removing the thrower from the coupler as indicated in Fig. 6. As in the arrangement shown, the surface 19 and the surface in the hole 23 are preferably coaxial and may have the same radius; the trunnions 20 and 24' then have a similar radius only slightly smaller than that of the bearing surface.

A front surface 17a of the lug 17 extends into close clearance with the rear tail surface 26 of the knuckle. The lug 17 is in approximate alignment longitudinally of the coupler with the shank wall 27. That is to say, a vertical plane passing through the axis 28 of the knuckle passes also approximately centrally through the bufiing lug 17 and the shank wall 27.

The bufling lug 17 substantially increases the capability of the coupler to withstand severe buffing forces, since it provides an obstacle to movement of the knuckle rearwardly in bufiing service in case the knuckle pin or interengaging knuckle and head portions fail under extreme load or become excessively worn.

The lug 17 functions also to minimize the damage to the coupler from. extremely heavy buffing shock sufiicient to damage or deform the parts which norm-ally take the buffing loads. The clearance between the knuckle tail and the bufling lug 17 may be made as small as desired to bring the buffing lug into operation at a relatively small degree of wear in the coupler.

Figs. 2 and illustrate the thrower 6 in an operative position at approximately the end of its thrower-opening stroke. Both figures illustrate the position of the thrower as the result of the vertical and horizontal forces acting on the lock-engaging arm of the thrower by the lower portion of the lock leg 30. Both trunnions are pressed rearwardly against their respective bearing surfaces and the thrower is lifted to bring end-thrust bearing structure into operation.

An-essential purpose of the present invention is to reduce the effort necessary in the knuckle-throwing operation by eliminating the frictional drag normally occurring between a thrower-retaining lug 34 of the thrower and a thrower-retaining abutment or undersurface 35 of the shelf 19. Accordingly, less clearance is provided between the top surface 37 of the trunnion 20 and the overhanging arcuate thrust bearing 21 than between the upper surface 34a of the retainer lug 34 and surface 35 of the shelf as found in the inoperative position of the thrower illustrated in Fig. 4. Thus, in the operative position of the thrower illustrated in Fig. 5, the trunnion top surface 37 is forced upwardly against the undersurface of the bearing flange 21 but clearance exists between the surfaces 34a and 35.

Because the surface 34a of the safety lug is held out of contact with the undersurface 35, and instead, bearing surfaces 37 and 38 of relatively small radius are subjected to the upward thrust of the thrower, the latter is rotated with but a fraction of the frictional resistance normally encountered in using the conventional thrower mounting comprising a bearing surface of relatively large radius, such as the undersurface 35.

While the undersurface 35 and the safety lug 34 function no longer as end-thrust bearing structure in the present invention, these elements are desired since they serve in an important manner to prevent accidental dis- I odgement. of the thrower from any position within its operative ambit in the coupler head. Dislodgement may voccur during violent upward impact, such as occasionally 3 and the lock 5 removed in the manner normally preceding the removal of the thrower. 'Ihe thrower may then be rotated counterclockwise to a position in which the safety lug 34 is completely removed from underneath the surface 35. The thrower may then be tilted forward as allowed by the clearance in the hole 23 for the pinion 24 until the trunnion end surface 37 no longer underlies the axial thrust bearing flange 21. The thrower is then readily removed from the coupler head by lifting it until the trunnion 24 is free of the hole 23.

Although the main embodiment of the invention is illustrated with the trunnion 20 having a bevel surface 40, such as is needed in some couplers to provide rotational clearance for the knuckle tail, this invention may well in clude such modifications as providing an end thrust hearing flange 21a- (see Fig. 7) of which its bearing surface for engaging the end of a trunnion 20a slopes radially inwardly and slightly in axial direction away from the end of the trunnion. In this installation, the flange would be thinner at the inner edge than at its junction with lateral bearing surface. Shown also in Fig. 7 is a trunnion surface of full circumference.

Fig. 8 illustrates that the end surface of a trunnion 20b may be slightly conical. This is especially suitable when using a flange 21 of uniform thickness, i.e., where the end-thrust bearing surface of the flange extends in a plane normal to its axis. However, the trunnions 20a and 20b are interchangeable with the bearings 21a and 21 of Figs. 7 and 8.

The terms and expressions'which have been employed are used as terms of description and not of limitation and there is no intention, in the use of such terms and expressions, of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the invention claimed.

What is claimed is:

1. In a knuckle-type car coupler having a head;" a knuckle thrower having an upper trunnion and a lower trunnion, both of which comprise coaxial lateral surfaces; the head having an upper bearing surface and a lower bearing surface spaced for engaging said trunnions and supporting the thrower for pivotal movement about a normally generally vertical axis; the upper bearing surface having an arcuate section complementary to a corresponding lateral surface of the upper trunnion of not greater than degrees in angular length, and an endthrust surface extending radially inwardly fnom the upper end of, and toward the axis of, said arcuate surface adapted for engaging the end surface of the upper trunnion; the lower bearing surface being substantially complementary to the lateral surface of the lower trunnion, but being slightly larger in circumference than the lower trunnion to provide clearance whereby the thrower may be tilted away from said arcuate surface and lifted upwardly and out of the head without interference with said end-thrust surface.

2. In a knuckle-type car coupler having a head; a knuckle thrower having an upper trunnion, a lower trun-. nion, and a thrower-retaining lug extending away from the pivotal axis of the trunnions at a level between those of the trunnions; the head having an upper bearing surface and a lower bearing surface for engaging said trunnions and adapting the head to support the thrower for pivotal movement about a normally generally vertical axis; means for limiting the ambit of the thrower to travel between a coupler-locked position and a coupler-open position; the head having a thrower-retaining abutment overhanging the space traversed by said lug within said ambit; said upper bearing surface having an arcuate section complementary to a corresponding section of the upper trunnion of not greater than 180 degrees angular length, and an end-thrust surface extending radially inwardly from the upper end of, and toward the axis of, said arcuate surface; the lower bearing surface providing lateral support in all radial directions with sulficient clearance with the lateral surface of the lower trunnion to allow tilting of the thrower away from said arcuate surface and lifting thereof upwardly and out of the head without interference with said end-thrust surface; said end thrust surface, in the normal coupler-closed position of the coupler, having less clearance with the end surface of the upper trunnion than said overhanging abutment has with the retaining lug.

3. In a knuckle-type car coupler having a head; a lock; a knuckle thrower having an upper trunnion and a lower trunnion both of which comprise arcuate coaxial surfaces; the head having an upper bearing surface and a lower surface spaced for engaging said trunnions and supporting the thrower for pivotal movement about a normally generally vertical axis; the upper bearing surface having an arcuate section complementary to a corresponding section of the upper trunnion of not greater than 180 degrees angular length, and an end-thrust surface extending radially inwardly from the upper end of, and toward the axis of, said arcuate surface; the lower bearing surface being substantially complementary to the lateral surface of the lower trunnion but being slightly larger in circumference than the lower trunnion to provide clearance allowing tilting thereof upwardly and outwardly of the head without interference with said end-thrust surface; said arcuate section of the upper bearing surface being slightly shorter than the upper nunnion, said thrower and said lock being arranged for the lock to exert a lifting force on said thrower to force the upper trunnion backwardly against said arcuate bearing surface section and upwardly against said end-thrust surface during a coupler-opening operation.

4. In a car coupler of the type provided with a pivotable knuckle having a tail portion; a head; a knuckle thrower having :an upper trunnion and a lower trunnion both of which comprise arcuate coaxial surfaces; said head having an inwardly extending integral projection, said projection-having an upper arcuate bearing surface complementary to a corresponding portion of the upper trunnion of no greater than degrees in angular length, an endthrust bearing surface extending radially inwardly from the upper end of, and toward the axis of, the arcuate surface, and a forwardly-facing bufiing surface disposed at close clearance with the opposing portion of the rearwardly-facing tail surface at coupler-closed position, said upper arcuate surface and said buffing surface being ad- 7 jacently disposed; the head having a lower bearing surface providing lateral support in all radial directions with sufficient clearance with the lateral surface of the lower trunnion to allow tilting of the thrower away from said arcuate surface and lifting thereof upwardly and out of the head without interference with said end-thrust surface.

5. The coupler of claim 4 wherein: the thrower includes a thrower-retaining lug extending away from the pivotal axis of the thrower at a level between those of the trunnions; said head is recessed under said projection and the supporting means has an undersurface extending radially outwardly from the lower end of said arcuate surface and overhanging the space traversed by the thrower-retaining lug during said ambit.

6. The coupler of claim 5 wherein: the end-thrust surface is spaced from the end surface of the upper trunnion at less clearance than that between said undersurface and the thrower-retaining lug.

References Cited in theme of this patent UNITED STATES PATENTS 2,695,713 Kayler Nov. 30, 1954 UNITED STATES PATENT OFFICE CERTIFICATION OF CORRECTION Patent N01, 2,948 4l5 August 9, 1960 William J. Metzger It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as.

corrected below.

Column 6,- line 29, for "supporting means" read projection Signed and sealed this 15th day of August 1961,

(SEAL) Attest:

ERNEST W. SWIDER Attesting Officer DAVID L. LADD Commissioner of Patents 

